Wrench.



C. T. HARNER.

WRENCH.

APPLIGATION FILED 001221, 1913 1,088,985. Patented Mar.3,1914.

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CLARENCE T. HARNER, OF SUVER, OREGN.

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Specification of Letters Patent.

Application filed October 21, 1913.

Patented lidiar. 3, i914. Serial No. 796,496.

To ZZZ whom t may concern.'

lle it known that l, CLARENCE T. HARNER, a citizen ot the United States, residing at Sliver, in the county of Polk, State of Oregon, have invented certain new and useful lmpriniements in Wrenches; and l do hereby declare the following to be a full, clear, and exact description ol the invention, such as will enable others skilled in the art t-o which it appertains to make and use the same.

This invention relates to wrenches and has .tor an object to provide a wrench having` jaws that will automatically grip nuts of various sizes without any adjustment of the jaws.

further object of the invention is to provide a simplified and improved spring controlled plunger device for Contact with a nut and operating to move the wrench aws into engagement with the nut.

With the above objects in view the invention consists of certain novel details of construction and combination of parts hereinafter fully described and claimed, it being understood that various modilications may be made in the minor details of construction within the scope of the appended claims.

ln the accompanying drawing illustrating this invention F igure l is a side elevation of a wrench embodying my improvements. lll ig. 2 is a side elevation with one of the side plates removed to expose the jaws and plunger. Fig. 3 is an end view. Fig. il is a longitudinal section on the line l l Fig. l.

Referring now to the drawing in which like characters of reference designate similar parts, the wrench is shown to comprise a handle l0 that terminates in an enlarged biiurcatcd head producing parallel side plates ll. A pair olz jaws l2 are pivoted intermediate the ends on pivot pins i3 carried by the side plates, the inner ends of the aws being connected by a helical spring la which is normally under tension and holds the jaws open.

Slidably mounted between the side plates is a plunger comprising a head 15, a reduced stem 1G, and a substantially triangularshaped cam 17 on the stem opposite the head, there being a longitudinal slot 1S in the stem which receives a transverse guide pin 19 carried by the side plates ll. A helical spring Q0 is seated on the stem and is confined under tension between the head l5 and guide pin 19, this spring exerting an outward pressure upon the plunger and nor mally holding the saine at its outward limit of movement with the apex of the triangular cani 17 disposed between and bearing lightly upon the adjacent inner edges of both jaws l2, said edges being cut away obliquely to provide cam surfaces 2l.

In operation, the wrench is applied to the nut by passing the jaws 1Q- on either side of the nut with the plunger head 15 bearing against the near face of the nut, the wrench being then forced snugly against the nut with a resultant urging of the plunger rearwardly whereby the trangular cam forces the rear ends of the jaws apart as it rides rearwardly on the cam surfaces 21 whereby the gripping ends of the jaws are locked into clamping engagement with the sides of the nut, the parts being returned to normal position upon retraction of the wrench from the nut as will be understood.

From the above description it will be seen that l have provided an extremely simple and inexpensive wrench that will automatically grip nuts of various sizes without any adjustment to the wrench aws.

W hat is claimed, is

l. A wrench including a handle having a bifurcated head providing side plates, a pair oit jaws ulcrumed intermediate the ends between said side plates, a helical spring connecting the rear ends of said jaws and normally holding said jaws open, and a spring pressed plunger slidably mounted between said jaws on said side plates and carrying an integral triangular shaped cam at the rear end engageable between the confronting edges of said jaws and adapted upon forcing of said plunger rearwardly to cam the rear ends ot said jaws apart and dispose the front ends of said jaws in clamping engagement with the sides of a nut.

2. ln a wrench the combination of a handle having a bifurcated head, a pair of jaws tulcrumed intermediate the ends in the biilfurcation of said head, a helical spring connecting the rear ends of said jaws and normally holding said jaws open, a stem in said bifurcation between said jaws having a longitudinnl slot, a head 0n one end of said spi-ing seated on said shank and confined unsteni for engagement with the nut to be deil tension between said head and said pin. le turned, n triangular shaped cani on the 0pn testimony whereof, affix my Signaposite end of said shank bearing upon ture, inthe presence Ot' two Witnesses. Obliquely disposed cani nees formed on the CLARENCE T. HARNER. inner edges of said jaws, a transverse pin Vlitnesses:

engaged through said slot and terminally C. N. DLoWMi-iN,

Secured in said bifurcation, and a helical J. D. VVINN.

Copies of this patent may 'be obtained for ve cents each, by addressing the Commissioner of Patents. Washington, D. C. 

